Good day, here it is:

link 1.hammer and cat's paw
The resemblance to a cat's paw is obvious.
I think the whole idea basically comes from this tool; tool first
fable second. (?) metaphor third.(or vice versa)

There's also a cat's paw nebula.
link 2. nebula

Last edited by BranShea; 01/11/2008 2:58 PM.